Fuel supply system for an internal combustion engine

ABSTRACT

The present invention relates to a fuel supply system for an internal combustion engine, accurate fuel injection may be attained every suction stroke of engine by the provision of a fluid element in a fuel injection control circuit. And the present invention is less cost, and is not influenced by vibration, heat, electromagnetic wave, and the like. In particular, with respect to the injection principle, there is not employed a mechanical method but collosion of liquid and gas so that atomization of fuel is greatly improved and combustion efficiency can be improved.

United States Patent 119 1111 3,874,352 Ishida 5] Apr. 1, 1975 FUELSUPPLY SYSTEM FOR AN INTERNAL 3,636,931 1/1972 Sada et a1 123/32 EACOMBUSTION ENGINE 3,695,245 10/1972 151m 123/119 R Inventor: TakashiIshida, N0. 649, Kamisi,

Oimachi, Ashigarakamigun, Kanagawa-ken, Japan Filed: Aug. 29, 1972 Appl.No.: 284,555

Related US. Application Data Continuation-impart of Ser. No. 91,618,Nov. 23, 1970, Pat. No. 3,695,245.

US. Cl. 123/119 R, 123/D1G. 10 Int. Cl. F02b 33/00, F02m 7/00 Field ofSearch 123/119 R, DIG. 10

References Cited UNITED STATES PATENTS 4/1955 ..123/119 R 11/1957 Whiteet a1 123/139 AW 2/1959 Olson 123/139 AW 3/1959 Dolza et al. 123/139 AWGianini Primary Examiner-Manuel A. Antonakas Assistant Examiner-DanielJ. OConnor Attorney, Agent, or FirmAndrus, Sceales, Starke & Sawall [57]ABSTRACT The present invention relates to a fuel supply system for aninternal combustion engine, accurate fuel injection may be attainedevery suction stroke of engine by the provision of a fluid element in afuel injection control circuit.

And the present invention is less cost, and is not influenced byvibration, heat, electromagnetic wave, and the like. In particular, withrespect to the injection principle, there is not employed a mechanicalmethod but collosion of liquid and gas so that atomization of fuel isgreatly improved and combustion efficiency can be improved.

7 Claims, 27 Drawing Figures PATENTED I T874352 sum mar 18- ATENIEDAPRH975 SHEET ESOF 18 PATENTED I975 SHEET 07UF 18 PMEMED APR 1 I975 SHEETQF L) PATENTED 1 5 SHEET 110F18 PATENTEU APR 1 1975 SHEET PATENTEU APR 3i975 SHEET PATENTED APR 1 i975 SHEET 150F18 mmi PATENTEB R 1 ms SHEET 180F 18 WNE PATENTEDAPR' 1 ms SHEET 170F 18 FUEL SUPPLY SYSTEM FOR ANINTERNAL COMBUSTION ENGINE This is a continuation-in-part ofapplication, Ser. No. 91,618 filed Nov. 23, I970, now U.S. Pat. No.3,695,245.

The present invention relates to a fuel supply system for an internalcombustion engine, and has its object to provide a fuel supply systemwherein accurate fuel injection may be attained every suction stroke ofengine by the provision of a fluid element in a fuel injection controlcircuit.

The fuel supply apparatus for an internal combustion engine has acarbureter system and an injection system. The injection system isroughly divided into a mechanical system and an electrical system. Asshown in FIG. 1, the mechanical system is to operate an injection nozzleby detecting number of revolution of engine, opening of air valve andpressure in the engine manifold and then inputing them into a mechanicalarithmetic unit. As shown in FIG. 2, the electrical system is to openand close a valve for a fuel injection nozzle by inputing the number ofrevolution of engine and manifold boosted pressure. However, in thiscase, unless injection is effected under the injection pressure of fuelof high pressure such as 23Okg/cm an error in injection amount becomesgreat under the influence of manifold boost. Particularly, in the caseof the mechanical system, considerably high accurate working is requiredwith respect to the mechanical computing device, fuel pump injectionnozzle and the like. Yet. when fuel flow is small in amount, forexample, in the case of idling, a satisfactory and ideal injection maynot be carried out and the stability in operation of engine is ofteninferior to carburetor.

In the case of an electric injection in which all circuits are formed byelectronics, there is a possibility of malfunction of an electriccomputing circuit under the influence of vibration, engine temperature,electromagnetic wave, and the like. It is natural that considerably fineworking is similarly required with respect to a nozzle portion.

This invention is proposed to remove disadvantages as described above.As shown in the block diagram of FIG. 3, a fluid element without havinga movable member in a part of arithmetic section, which controlsinjection of fuel, is either used, or the fluid element and anelectronics circuit are used so that fuel may be injected every suctionstroke of engine by utilization of air pressure for on and off operationof fuel at the injection part. With such a construction as above, thepresent invention is less cost in manufacture than that of injectionsystem heretofore used, and is not influenced by vibration, heat.electromagnetic wave, and the like. In particular. with respect to theinjection principle, there is not employed a mechanical method butcollosion of liquid and gas so that atomization (pulverization) of fuelis greatly improved and combustion efficiency can be improved, coustingcut is much more simpler than engine provided with a carburetor, havingsuch effects as reduction in cost of fuel, reduction in waste noxiousmatter, and the like.

Generally, the fuel flow characteristic of reciprocating engine can berepresented by two factors, number of revolution of engine and manifoldboosted pressure. Therefore, fuel consumption is either given as shownin FIG. 4 fuel consumption to number of revolution of en gine withboosted pressure as a parameter, or as shown in FIG. 5 fuelv consumptionto boosted pressure with number of revolution of engine as a parameterto thereby make possible to cover the whole range of operatingconditions.

For this reason, fuel flow can cover the whole operation by forming afunction to number of revolution of engine and a function to manifoldboosted pressure. In accordance with the foregoing conception, thepresent invention is to control fuel injection wherein the number ofrevolution of engine is detected by air pressure and electrically, andsaid detection and manifold boosted pressure are inpect into an airpressure system arithmetic circuit.

The present invention will be illustrated with reference to theaccompanying drawings;

FIGS. 1 and 2 are block diagrams of a fuel supply system heretoforeused;

FIG. 3 is a block diagram of the same according to the presentinvention;

FIG. 4 is a curve showing fuel flow characteristics with engine manifoldboosted pressure as a parameter;

FIG. 5 is a curve showing fuel flow characteristics with number ofrevolution of engine as a parameter;

FIGS. 6 to 9 illustrate one embodiment in which FIG. 6 is an overallcircuit diagram, FIGS. 7 and 8 are longitudinal sections showing a fuelinjection element in FIG. 6 mounted on the engine manifold or manifoldtake pipe, and FIG. 9 is an enlarged section showing a fuel injectionnozzle portion;

FIG. 10 is an enlarged explanatory view ofa detector portion of numberof revolution for engine;

FIG. 11A is an output diagram of a one shot circuit in FIG. 10;

FIG. 11B is an output diagram showing results of output obtained byoperation of collosion element;

FIGS. 12 and 13 are modified circuit diagrams of a mixed air supplystage;

FIG. 14 is an overall circuit diagram showing the second embodimentaccording to the present invention;

FIGS. 15 and 16 are longitudinal sections showing a fuel injectionelement in FIG. 14' mounted on the engine manifold or manifold takepipe;

FIGS. 17 and 18 are modified circuit diagrams of a mixed air supplystage;

FIG. 19 is an overall circuit diagram showing the third embodiment withthe detector portion of number of revolution for engine replaced byelectronics;

FIGS. 20 and 21 are modified circuits of the mixed air supply stage inFIG. 19;

FIG. 22 is an overall circuit diagram showing the fourth embodiment withthe detector portion of number of revolution of engine replaced byelectronics;

FIGS. 23 and 24 are modified circuit diagrams of a mixed air supplystage in FIG. 22;

FIG. 25 is another modified circuit diagram of the detector portion ofnumber of revolution of engine in FIG. 6;

and FIG. 26 is another circuit diagram of the detector portion of numberof revolution of engine in FIG. 14.

The embodiments according to the present invention will now be describedwith reference to drawing. FIG. 3 is a block diagram according to thepresent system, diagramatically showing the status in which detectionvalve of number of revolution of engine and detection valveof manifoldboostedpressure are input into an arithmetic circuit, and controlledamount is fed into an engine manifold through a fuel injection element.

1. A fuel supply system in an internal combustion engine comprising a fuel injection element mounted within the engine manifold and forming a transverse impact modulator having first and second supply nozzles opposedly disposed one nozzle of which introduces compressed air and the other nozzle of which introduces fuel to form opposing impacting air jet and fuel jet, said transverse impact modulator having a drain for the fuel jet which is to be drained when injection is not required, a control means connected to said supply nozzles to control the relative strength of said jets of said fuel injection element, said modulator having a control jet nozzle formed at a right angle in the vicinity of the first main supply nozzle and engaging the jet to deflect relative to the opposing jet, a normal running stage circuit means having a pulse output related to the number of revolutions of said engine and connected to said control air jet nozzle of said fuel injection element as a pulse signal, and a mixed air supply stage circuit means connected to said opposed nozzles which supply fuel and air to said fuel injection element and having a control valve means actuated in response to the negative pressure of engine manifold to control the relative supply of fuel and air to said fuel injection element.
 2. The fuel supply system according to claim 1, having a coasting cut stage circuit including a fluidic proportional means coupled to the nozzles to establish a control signal, and a transverse impact modulator having a control jet nozzle connected to said proportional means and having an output means connected to the control nozzles of the fuel injection element controlling the injection of fuel when in coasting operation of the engine.
 3. A fuel supply system according to claim 1, wherein said normal running stage circuit means including an electronic signal forming means producing a series of pulses in response to the crank shaft of the engine and having time width which is in iNverse proportion to the speed of rotation of the engine, and a solenoid valve connected to the pulse forming means and having an output connected to said air jet nozzle so as to control the air pressure pulse supplied to the fuel injection element.
 4. The apparatus of claim 1 wherein said fuel injection element is mounted with nozzles parallel to the manifold and establishing opposing streams parallel to the fluid flow through the manifold.
 5. A fuel supply system in an internal combustion enging comprising a fuel injection element mounted within the engine manifold and being a summing impact modulator having nozzles opposedly disposed one nozzle of which introduces essentially only compressed air and the other nozzle of which introduces fuel to form an impacting air jet and fuel jet, a control means to control the relative strength of said jet of said jet of said fuel injection element, said summing impact modulator having a drain means for draining of the fuel jet when injection is not required, a normal running stage circuit means having a pulse output related to the number of revolutions of said engine and connected to said control means for said fuel injection element as a pulse signal, and said control means is coupled to vary the pressure level of the air jet pulsewise between low or high when in response to injection of a pulse signal output in the normal running stage circuit, a mixed air supply stage circuit means connected to said opposed nozzles which supply fuel and air to said fuel injection element, a coasting cut stage circuit means coupled to the nozzles and controlling the injection of fuel when in coasting operation of the engine, said air jet having a controlled pressure by means of an air pressure control valve in the mixed air supply stage circuit and by controlled pressure means in the coasting cut stage circuit.
 6. A fuel supply system in an internal combustion engine comprising a fuel injection element mounted within the engine manifold and having a pair of opposed nozzles opposedly disposed and one of which is connected to introduce essentially only compressed air and the second of which is connected to introduce fuel to form opposed and impacting air and fuel jets which impact within the engine manifold and having a control means for controlling the relative strength of said jets and the position of impact, air supply means coupled to the first of said nozzles, fuel supply means coupled to the second of said nozzles, a control means for controlling the relative strength of said jets, and a normal running stage control means connected to the engine and establishing a pulsed output control signal in accordance with the operating speed of the internal combustion engine, said normal running stage control means including a rotating control means coupled to the engine and rotated in synchronism therewith, said rotating control means having a fluid supply means establishing a fluid stream and means responsive to the speed of the rotation to interrupt said stream and establish first and second time spaced fluid control signals, the first of said time spaced fluid control signals having a predetermined width adapted to establish a corresponding on-off control signal to the fuel supply control means, connecting means connecting said first time spaced fluid control signal to said control means, and means connecting the second of said time spaced fluid control signals being interconnected to said connecting means to modify said first timing control signal to produce a predetermined variation in the width of said first timing control signal and to thereby control the fuel injection control element in an inverse proportion to the speed of the rotation of the engine to control the air fuel mixture supplied to the engine in accordance with the speed of the engine.
 7. The apparatus of claim 6 wherein said rotating control means includes a rotating element located between a supply nozzle and a receiving nozzle having a pair of physically spaced coupling openings, said nozzles and said stream aligned with said openings and interrupted by the element and sequentially coupled to the corresponding opening to thereby produce corresponding said first and second time spaced output signals for each revolution of the rotating element. 